The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 29, 2006
Filed:
Apr. 18, 2003
Ching-yu Chang, Yilan Hsien, TW;
Hsin-huei Chen, Miaoli, TW;
Meng-wei Chen, Changhua, TW;
MACRONIX International Co., Ltd., Hsinchu, TW;
Abstract
A method of reducing a critical dimension ('CD') bias between a dense pattern and an isolation pattern is disclosed. The method includes a first step of providing a mask having a dense pattern, an isolation pattern and the other area of the mask is transparent, in which mask the dense pattern has a first opaque pattern and the isolation pattern has a second opaque pattern. The second step of the method is forming a virtual pattern around the isolation pattern, in which a distance between the virtual pattern and the isolation pattern is y, and the virtual pattern has a pattern line width x. By forming the virtual pattern around the isolation pattern, the flare effect of the isolation pattern is close to that of the dense pattern, thus the CD bias between a dense pattern, and an isolation pattern is reduced, and the process window does not shrink.